1. Technical Field
This disclosure relates generally to combustors for gas turbine engines and, more particularly, to the configuration of quench apertures in a combustor for a gas turbine engine.
2. Background Information
A typical combustor in a gas turbine engine has a combustion chamber having a forward section, an intermediate section (sometimes referred to as a “quench section”) and an aft section. The combustion chamber includes a forward bulkhead, an inner annular wall and an outer annular wall which extend from the forward bulkhead to an exhaust outlet. The forward section of the combustion chamber includes a plurality of circumferentially disposed nozzles and swirlers. The intermediate section of the combustion chamber includes a plurality of equally spaced quench apertures circumferentially disposed in the inner and outer walls.
In operation, fuel from the nozzles is mixed with air from the swirlers and ignited by an ignition source in the forward section of the combustion chamber creating thermal hotspots circumferentially aligned with the nozzles. As known in the art, a thermal hotspot is a region in a thermal profile where the temperature is significantly elevated as compared to the surrounding area of the profile. The ignited fuel-air mixture flows from the forward section into the intermediate section where the mixture is quenched by additional air (“quench air”) flowing into the chamber from the inner and the outer quench apertures. The quench air performs two functions: it provides oxygen for completion of combustion, and it is used to affect the shape of the thermal profile. The quenched mixture flows from the intermediate section, through the aft section, and out of the combustor through the combustor exit. However, the exhausted combusted mixture may still exhibit significant thermal hotspots which reduce the efficiency of the engine.